Police have uncovered a sophisticated methamphetamine lab in six shipping containers and three caravans and seized guns, explosives, surveillance equipment and ingredients to make P.

On Friday the Armed Offenders Squad, a clan lab team, police officers and the defence force bomb disposal squad simultaneous raided properties in Auckland's Blockhouse Bay and Ngaruawahia where they uncovered the P lab.

The clan lab team "meticulously searched and processed" the lab over the weekend after AOS members secured the property about 4pm on Friday.

Detective Sergeant Nina Pedersen of Avondale CIB said police had found a rifle, subsonic ammunition, flares, grenades and explosives at the property in River Rd, Ngaruawahia.

"This has been an inter-district operation and I'm very proud of the way all officers have worked together at short notice to shut down what experienced clan lab staff described as a sophisticated commercial-scale laboratory set up to supply large amounts of illegal class A drugs."

Two Auckland men, David Griffiths, 37, and a 43-year-old, were found at the River Rd property and were charged with manufacturing methamphetamine.

A woman arrested at the Blockhouse Bay Rd property was charged with possession of a class A drug and possession of class C drugs for supply.

Griffiths has appeared in court and was remanded in custody to reappear on October 30.

The other man has been bailed to an Auckland address and will re-appear in court on the same date.

Pedersen said further arrests were likely.

- © Fairfax NZ News